from time import sleep
class Clock(object):
    def __init__(self,hour=0,minute=0,second=0):
        self._hour=hour
        self._minute=minute
        self._second=second
    def run(self):
        self._second+=1
        if self._second==60:
            self._second=0
            self._minute+=1
            if self._minute==60:
                self._minute=0
                self._hour+=1
                if self._hour==24:
                    self._hour=0
    def show(self):
        return '%02d:%02d:%02d'%\
               (self._hour,self._minute,self._second)

def main():
    clock=Clock()
    cycle_num=int(input('请输入循环次数：'))
    for x in range(cycle_num):
        print(clock.show())
        sleep(1)
        clock.run()
if __name__=='__main__':
    main()

